P2129 serious

Throttle Actuator Control Motor Current Too High

The P2129 code means the vehicle's onboard diagnostic system has detected: Throttle Actuator Control Motor Current Too High. This is a serious severity code.

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Keep driving?
Short distances only
DIY difficulty
Advanced
Estimated cost
$300 - $700 (parts and labor)
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Common Symptoms

  • Check Engine Light illuminated
  • Vehicle enters reduced power or limp mode
  • Throttle response severely limited
  • Engine may stall unexpectedly
  • Burning smell from throttle body area in severe cases

Probable Causes (Ranked by Likelihood)

  • Throttle actuator motor internal short circuit High
  • Mechanical seizure or binding of throttle plate High
  • Short circuit in throttle motor wiring harness Medium
  • Excessive carbon buildup creating high motor resistance Medium
  • PCM over-driving the throttle motor circuit Low

Step-by-Step Diagnostic Procedure

  1. Scan for codes and confirm P2129 - note any accompanying throttle codes

  2. Measure throttle motor current draw with a clamp meter - compare to specification (typically under 3A)

  3. With engine off and key removed, manually move the throttle plate to check for binding

  4. Check throttle motor winding resistance for signs of internal short (lower than spec resistance)

  5. Inspect all wiring between PCM and throttle body for chafing, melting, or shorts

Frequently Asked Questions

What does P2129 mean?

P2129 means the PCM has detected excessive current draw from the electronic throttle actuator motor. The motor is drawing more electrical current than its design limit, indicating a potential short circuit or mechanical problem.

Is P2129 urgent?

Yes. Excessive motor current can cause overheating of the throttle body or PCM driver circuit. While the vehicle will enter limp mode for protection, continued driving risks component damage. Have it repaired promptly.

How much does it cost to fix P2129?

Repairs typically cost $300 to $700. Most cases require throttle body replacement at $300-$600. Wiring repairs are less common but cost $150-$350.

Sources

This page is built from documented references. Verify against your own service info before repair work.

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